Alloy



high-speed cutting tools and'the like which" Patented Sept. 11,1928.

umrao ST A 1. .1 1 TES PATENT OFFICE.

:eUssELL FRANKS, or ELMIIUBST, Ann 11mm 11. HELD, or 'nouenns'romnnw YORK, assrenons 'ro mamas srnmrra COMPANY, A. conrdanrron or mnmmt l io nra'wing Original applieationfiled January. 8, 1925, Serial No. 1,305. Divided 'fl1ed March 5, 1926. Seria1 No. 92,584.

' Our invention relates to alloys for use as are similar in general physical properties and structural characteristics to those obtained by H. S. Cooper, U. S. Patents Nos. 1,221,769, 1,277,0ie, 1,278,304., 1,350,359 and 1,161,178. a

Our new alloys contain as essential components nickel or cobalt. in preponderatin proportion, usually substantialamounts 0 tungsten, small amounts of boron up to about 1%, and substantial amounts of ti- Ytanium. .minum are usually present and have more or less effect onthe. properties of the alloy.

Molybdenum or uranium may be present,- 7 replacing part or all of the tungsten. Heretofore in' preparing alloys such-as those. disclosed by Cooper in the patents above mentioned, the desired hardnesjrhas been obtained by adding a consid able amount of aluminum over and above that contained ,in the alloys used as raw materials. A great deal of trouble was encountered through oxidation of this excess aluminum and in addition the tungsten segregated very rapidly as soon as the aluminum was added. We have now producedalloys.

of this type in which, hardness and good cutting properties are secured by raising the titanium content and correspondingly decreasing the aluminum oxidation of aluminum and the segregation of tungsten are largely avoided.

We have found t at the-hardness of-the alloyis increased by the presence of boron therein, and that there is a marked refinement of grain. the boron seems to actin conjunction with the titanium ,in' producing a much better cutting tool than can be made from alloys of this type which do not contain boron.-

Alloys made inaccordance with our invention have a preferred composition range of 5 to 12% tungsten, 6 to. 12% titanium, 3.5 to 6% silicon, 3 to 5% aluminum, up to 1% boron, with the balance principally nickel or cobalt. The boron may be added in the form of" ferro-boron, chromiumboron, boron carbide or any other "suitable alloy of boron. mium-boron-is used, small am'o'untsof iron or chromium will be introduced into; the

final alloy, but these have no appreciable Minor amounts of silicon and alu-f boron 0.55%, nickel remainder.

content, whereby We have also found that When ferro-boron or chro.-

and um nimation efi'ect on-its properties. The other raw materlals frequently contain small amounts of iron -so that the iron 'content of. the final Y boroncontaining materials together in a graphite cruclble in any suitable type oi"- furnace, raising the temperature of the molten bath to .1600-1800 C., and then stlrring the titanium in the form. ofsome' suitable titanium alloy into the melt. The

titanium alloy will dissolve quite readily if vlgorous stirring "is employed. The melt may be poured at once into sand, carbon, or

graphite molds. A titanium alloy whichhas given good results in this work contains 64.8% tltanium, 27.3% aluminum, 2.2% silicon, 21% iron and 1.0% carbon. It is friable and ma *be'crushed to a powder. The best results ave been obtained .when it was crushed to approximately 40 mesh. No aluminum except that contained in the titanium .alloy is added to the melt. One melt of this cutting tool alloy which has the proper hardness and good cutting quality had the following composition: tungsten 7.23%,titanium 7.20%, aluminum 3.90%,

silicon 4.40%, iron 0.95%, carbon While in theexamples above given nickel has been specified as the principal.constituentof the alloy, itis to be understood that cobalt-may be. substituted for nickel or used with the same, and that nickel is useddn the claims-[to mean either nickel or cobalt 'or both. Y

In our application,

have somewhat broadly 1s a division, we

claimed alloys of thisclass containing boron and either titanium or zirconium, and we have also claimed specifically such of said alloys as are characterized by the. use of boron and zirconium.

All the alloys comprised within the invention are suitable for tools for the high--' of cast iron, steel and" semithey are also useful for'other, high-speed is here used in the same sense as in the common expression speed cutting steel, though purposes. The term high-speed steel, and imports conditions 10f such (severity carbon steels subjected to them would be Serial No. 1,305, filed I January 8, 1925, of which this application,

that ordmary .6 to 12% titanium,

for" the high-speed cutting of cast iron which contains 3% to 5% of aluminum, 3.5% to 6% of silicon, 5 to 12% of tungsten, -S to 12% or titanium, and approximately 0.5% of boron, with the balance principally nickel. v

3. A cutting tool composed ofan alloy containing from 3 to 5% aluminum, 3.5 to 6% silicon, 5 to' 12% tungsten, 6 to 12% titanium, boron in substantial and effective amounts up to 1%, cipally nickel.

In testimony whereof, We aflix our signatures.

the balance being prin- RUSSELL FRANKs. BURNHAM E. FIELD. 

